冷冻干燥法制气凝胶

UniversityofScienceandTechnologyofChina1.Introduction2.SynthesisofUFA3.Freeze-dryingtechnique4.Conclusion1.IntroductionAerogelMechanicaPropertieslElectricalConductivitiesThermalAcousticLargeopenporesandHighinternalsurfaceareaLowDensitySynthesisbyFreeze-dryingtechniqueHaiyanS，ZhenX，ChaoG.AdvancedMaterials.2013,25:2554-2560.Multifunctional,Ultra-Flyweight,SynergisticallyAssembledCarbonAerogelsCNTsaqueousdispersion1.0mg/ml，28mlGGOaqueousdispersion1.0mg/ml，28mlMixingStiringfor1.5h2.SynthesisofUFAHaiyanS，ZhenX，ChaoG.AdvancedMaterials.2013,25:2554-2560.mixturemoldfreeze-dryingfor2dchemicallyreducedbyN2H4vaporat90℃for24hvacuum-dryingat160℃for24hMechanism:waterbecameice，thenvapored,leftmanyvoidsmolddecidestheshape2.SynthesisofUFAHaiyanS，ZhenX，ChaoG.AdvancedMaterials.2013,25:2554-2560.2.SynthesisofUFAHaiyanS，ZhenX，ChaoG.AdvancedMaterials.2013,25:2554-2560.(d)(c)(e)(f)HaiyanS，ZhenX，ChaoG.AdvancedMaterials.2013,25:2554-2560.2.SynthesisofUFA冷冻干燥（Freeze-drying）又称真空冷冻干燥、冻结干燥、冻干（FD）。1811年诞生，用于生物体脱水1890年医学上的首次应用，冻干了一批生物器官1932年引入真空设备，在生物制品、药剂以及食品领域迅猛发展1935年干燥的过程采用主动加热，开始应用到工业生产1965年首先采用冻干技术制备出金属超细粉末如今在超导材料、超细金属粉末、精细陶瓷、催化剂、高能电池以及薄膜材料等领域都得到了广泛的应用。孙启达,冷冻干燥超细粉体技术及应用[M].化学工业出版社,2006.HistoryofFreeze-drying3.Freeze-dryingtechnique3.Freeze-dryingtechniquePhasediagramofsalt-watersystem3.Freeze-dryingtechniqueHighlyelasticgrapheneoxide–epoxycompositeaerogelsviasimplefreeze-dryingandsubsequentroutinecuringShibingYeetal,J.Mater.Chem.A,2013,1,3495–3502SEMimagesof(aandb)GOAand(candd)GEA-9MultifunctionalGraphene/Platinum/Nafion（全氟磺酸）HybridsLuisEstevezetal.J.Am.Chem.Soc.2011,133:6122–6125MultifunctionalGraphene/Platinum/NafionHybridsviaIceTemplatingJustinE.Silpe,etal.Langmulr,2013,29:8782-8787.Freeze-dryingAntibubblesfabricatedbyFreeze-dryingmethodFreeze-dryingsynthesisofLi3V2(PO4)3/CcathodematerialTheas-preparedmaterialshowsauniformparticlesizedistributionandtheparticlesizeismuchsmallerthan300nm.thecompositedeliveredareversiblecapacityof125.2mAhg-1withoutobviouslyfadingafter100cycles.QiaoYQ,WangXL,MaiYJ,etal.JournalofAlloysandCompounds,2012,536:132-137.徐如人,庞文琴,霍启升.无机合成与制备化学[M].高等教育出版社,2009.Saltsolution（orcolloid）Spray-freezingCongelationMetalsaltballCompositeOxidesOxides,Matelultra-finepowdersVacuumdryingPyrolyzationorothertreatment3.Freeze-dryingtechniquePrepareultra-finepowderAdavantages：1.Canbeobtainedinahomogeneousmixtureofthecomponentsinsolution,suitableforaddingtracecomponents,synthesizecomplexfunctionalceramicmaterialsnanoparticles.2.Sizeofnanoparticlesrangefrom1nmto50nm.3.Easytooperateandgoodinthepreparationofhighpurityceramicmaterial.Disadvantages：Efficiencyisrelativelylow,corrosivegasimpactthelifeoftheequipment.3.Freeze-dryingtechnique4.ConclusionTheprincipleofFreeze-dryingtechniqueSynthesisofAdvancedMaterialsbyFreeze-dryingtechniquehasmanyAdvantages:template-freesimpleretaintheoriginalstructurescalablefabricationEnlightenment:newwineinanoldbottle;newconceptsinanoldframework1.孙启达,冷冻干燥超细粉体技术及应用[M].化学工业出版社,20062.徐如人,庞文琴,霍启升.无机合成与制备化学[M].高等教育出版社,2009.3.HanY,XuZ,GaoC.Ultrathingraphenenanofiltrationmembraneforwaterpurification[J].AdvancedFunctionalMaterials,2013.4.EstevezL,KelarakisA,GongQ,etal.Multifunctionalgraphene/platinum/nafionhybridsviaicetemplating[J].JournaloftheAmericanChemicalSociety,2011,133(16):6122-6125.5.MecklenburgM,SchuchardtA,MishraYK,etal.Aerographite:UltraLightweight,FlexibleNanowall,CarbonMicrotubeMaterialwithOutstandingMechanicalPerformance[J].AdvancedMaterials,2012,24(26):3486-3490.6.SchaedlerTA,JacobsenAJ,TorrentsA,etal.Ultralightmetallicmicrolattices[J].Science,2011,334(6058):962-965.Citation